Sack inverting machine



Sept. 20, 1932 J. K. FOLKER Em.

SACK I-NVERTING I MACHINE Filed Aug. 31, 193} 4 Sheets-Sheet 1 In Illlllllll Sept. 20, 1932.

4 Sheets-Sheet 2 FIG. 2.

Sept. 20, 1932. J. K. FOLK ER ET An. 1,873,627

SACK INVERTING MACHINE FiIed Aug. 51, 1931 4 Sheets-Sheet 5 tion pipes located the one above and the other Patented Sept. 20, 1932 UNITED srA n fs r rsNr J'OHANNES KRISTIAN FOLKER, ;OF CHARLOTTENLUND,,AND FRED'ERIK TRUELSEN, F COPENHAGEN, DENMARK FERDINAND SACK Invnn'rme MAoniNn Application filed August 31 1931, sees no.

being subsequently inverted manually "over asuitable buckor the like. However, in wholesale manufacture this method is uneconomical 1 and causes loss of time.

The present invention relates to am'achine adapted to invert the sack or bag without any manual operation being required with exception of the placing in the machine-of the sack or bag.

The machine according to the present 'invention operates in-the following manner: The sack placed upon a table of-the machine is opened by meansof suction from two sucbelow the sack. Two grippers in'the' machine are subsequently introduced into the opened 7 sack so as to stretch the same and on their return movement said grippers will draw the stretched-out sack on to a pivotable turn-over v buck in the free end of which an opening is formed. When the sack has been drawn on to said turn-over buck the free end of the latter will swing downwards'and will be stopped in this movement at the level of a turn-over fork which is subsequentlymoved to the bottom of the-sack from which position it will press said bottom into the sack through the open ing in the end of the turn-over buckso that the sack will now rest outside out. on the turnover fork. The sack is now caught and held by a clamping device, so that it will, on the turnover forkreturning andthe turn-over V buckswinging upwards, be made free from the turn-over fork by being drawn oii" the latter and will, as the clamping device simultaneously releases its hold on the;sack,-drop down into a collector. V

A form of execution of the invention is y ofexample u ratedin themings vhere *Fig. 1 shows a sack inverting machine according to the present invention inside view, a'few'parts being removed so as to clearly show the single members,

560,464, and in Germany February s, 1931. Q

FigQshows the machine in Fig. 1 in top I Fig-dis a perspective drawing of the turn Over buck and turnover fork of the machine,

Fig. 4 is asect-ion, at a larger scale,along the line IV-IV in Fig. 2,

Fig.; is-a section at a larger scale through the suction device along the linegV-V in Fig. 1, 1 1

Figs. 6, 7, 8, 9 and show diagrammatically therelative positions of the sack, the turn- 7 overbuck and the turn-over fork at various stages of the inverting operation.

1 indicates a machine frame carrying the several members. 2 is a turn-over buck which consists (Fig. 3) of a frame 3 to the-underside of which two side plates 4 are welded and connected at the closed end of said frame l 3 to a bridge 5 provided centrally 'with a" resilient flap 6. A square opening is thus formed at the end of the turn-over buck. The one end of the frame 3 is secured to a sleeve 7 which latter is secured to a shaft 8 (Fig. 1).

The shaft 8 carries outside the machine frame 1 a long downwardly extending arm 9 secured to the end of said shaft so that a swinging movement of the arm 9 will cause the freev endof the'turn-over buckto be lifted or lowered. The shaft 8 is journalled in bearings 10 in the frame 1. .The swinging movement ofthe arm 9 is brought about by means of a rod 11 and a lever 12 the arms of which form an obtuse angle. An oscillating movement is imparted to'said lever 12 by means of a roller 13 secured thereto and contacting with the circumference of an eccentric cam 14 secured to a tooth wheel 15. Said: tooth wheel 15 is operated by a pinion 16 on the machine driving shaft 17 which latter may be driven,

for example by a pulley 18 receiving the driving power froma motor, a'gear transmission or other suitable source. Instead of using the pulley the driving shaft may receive the power, through a suitable clutch, from an electric motor mounted on the machine frame.

19 indicates a turn-over fork (Fig. 3) and consists of a stem 20 secured at its one end to V a slide 21 (Fig. 2) adapted to slide in guides or the like at the top oftheframe 1. i The'stem 20 v carries in its free end a cross piece 23 i said slide 40.

provided with a central recess 24. The stem carries almost centrallv two arms on the ends of which two rods 27 actuated by springs 26 are adapted to oscillate. Said rods 27 are S-shaped and are attheir free ends provided with rollers 28 which, when the rods are pressed against the stem 20, rest in two SGIIll-ClI'ClllfiI, recesses 29 1n the ends of the cross piece 23. During the operation of the machine the rods 27 are pressed against the stem 20 by means of'two rollers 30' provided in a bar 31 (Fig. 1) secured to the frame 1.

The slide 21 and thus theturn-over fork, are

adapted to be reciprocated along'the guides 22 offtheframe by means of an arm 32 rotatably secured to a mounting 33 on theslide 21 and adapted to oscillate in the machine frame around a pin 34. The reciprocating movement of'the arm 32 and thus of the slide 21 is produced bv a crank arm 36'driven by a crank keyed to a shaft 37 which latter carries the-above mentioned tooth wheel 15 The shaft 37 is journalled in bearings 38 in The slide 40 has a cross bar (Fig. 2) to whichltwo grippers 46 are secured'which are each in the shape of a single-armed lever oscillating around a pin in bearings 47. The saidgrippers serveto hold' the open end of the sack stretched to a suitable degreesubsequent to the two parts of the mouth of the sack having been removed from one another by means of thesuction to be described later;

on. When this has taken place the grippers 46 areintroduced into'the mouth of the sack and the height of said grippers is so adjusted that the sack mkouth during the stretching operation will remain large enough to allow it of being drawn on to the turn-over buck. The free ends of the two grippers are forced away from one another by means of two twisting springs located in housings .48 (Fig.

. 1) on the'bearings 47. Thegrippers are provided with a central outwardly projecting arm having a roller 4700. I

Areciprocating movement is imparted to the arm 41 and thus to the slide 40 by means of 'apull rod 49 the one end of which is rotatably connected to a pin 50 eccentrically disposed on-the tooth wheel 15. I

The one of the guide lists 39 carries a bearing-51.(Fig..1) for a pin of'a bell cranklever 52the long arm of which carries in its eX treme free end an upper suction pipe posi-V tioned laterally over the machine and'having two suction fittings 53a (see Fig.v 5) the mutual distance'of which corresponds to the width of the sack to be treated. The pipe 53 has a fitting 54 (Fig. 1) from which a hose leads to a suction pump 56 mounted on the frame and driven in any suitable manner,

forexampleby the arm 32.

The bell crank lever 52 together with the suction pipe 53 are adapted to oscillate up and down by means of a pull rod 57 (Fig.1) rotatably connected to an arm;58 having a roller'59.

The lower end of arm 58 is pivoted in a bearing 60 on the frame. The roller bears against and is moved up anddown by an eccentriccam 61 on shaft 37.

A;clampingdevice,for holding. the inverted sack or bag is provided centrallyon a cross bar 62 on the frame 1 and below the shaft8 carrying theturn-over buck 2.,

in Fig.4, comprises an arm 63 pivoted atits lower end in a bearing in the frame, while the upper end of said'arm forms the one jaw 64 of the clamping device. The arm 63 carries a double-armed lever 65, 66 theone arm 66 ofwhichforms the other jaw of the clamping device... The arm 65 has a stop 67. The

lever 65f66 ispivotable around a'pin' 650; in the arm63 and a spring located in a housing 68 tends to press the jaw 66 against the jaw 64. The arm 63 also carries a' movable arm 69 provided at its top with a shoulder 7 0 corresponding inshape to the stop 67 on the arm 65. Arm 69 carries a fixed releasing arm 69a. To the'frame there is mounted a fixed tensioning arm'71 having a roller 72 at its top end. The upper end of a bell crank lever 73, 73a. (Fig. 1) rotatable in .a bearing Men the frame is connected by a pull rod 75 to the arm 63 and the lower arm 73 of said lever is connected by a rod 76-to the arm 41 Said clamping device which is illustrated so that-when the latter is being moved (to-' wards the left in Fig. 1) the pull rod 75 and thus the arm 63 will be moved downwards.

A spring 77 is provided between the tension ing arm 71 and the'upper arm 73a of the bell crank lever which spring tends toraise said arm 7 3a and thus the rod 7 5 and the arm 63. 'The rod 76 is slidable in a rotatable bearing'78 on the arm 41 andhas a shoulder 7 8a which will on thearm 41 returning (to- Wards the left in Fig. 1)v with the slide 40,

abut against the bearing 78 and will thereby, by way of the rod 7 6 force downwards thef upperarm of the bell crank lever 73 together with the pull rod 75 and the arm 63 causing that the arm 65' of'the lever 65, 66 mounted on arm 63 is forced upwards with the result that the stop 67 engages the shoulder 70 thus holding the jaw 66 in its open position.

7 Two arms 80 (Fig. 2) actuated by springs 79 pivotable at their front end in'bearings 81 are mounted at the top internally on the longitudinal girts of; the frame. The arms 80 are in reality doube-armed levers the short e1!" arms of which are cut away on the lower half part and which lie in the: path of the rollers 41w on the grippers 46 which rollers are movable together with the slide 40. Gonsequently; the roller" i702 Willduring the forward movement (to the right in F ig. 2) of the slide 40 slide along the internal faces of the arms 80. On the roller Ha reaching the cut away portion of the shorter arm of the arm 80 it will slip onto the external face of the arm 80 and will during the returning movement of the slide 40 pass along the external face of the spring actuated arm 80.

82 is a collecting table for the sacks or bags to be inverted by the machine.

A lower suction pipe 83 is mounted under the collecting table 82 and immediately below the upper suction pipe 53. The two suction fittings 84 (Fig. 5) of said lower suction pipe 83 are disposed immediately below the suction fittings 53a of the suction pipe 53 and extend upwards through openings in the collecting table to the level of the top. face of the latter. The lower suction pipe 83 communicates through a hose with the air pump 56.

The mode of operation of the machine is as follows with reference to Figs. 6 to At the commencement of the operation'the sack or bag 90 to be inverted is placed on the table 82 its open end under the upper suction pipe 53; The latter is now lowered down to the sack due to the actuation of the lever 52. The suction pump 56 is placed in such a manner relatively to its driving member that the suction will commence just at that moment.

During the movement of the lever 52 the upper suction pipe 53 will raise the side of the sack next thereto while the other side of the sack is held against the collecting table due to the suction from the lower suction pipe 83. Consequently, the mouth of the sack will be opened, Fig.

The conditions are so that the slide 40 (Fig. 2) will simultaneously be moved up along the guides 39 under the influence of rod 41. The rollers 47a on the grippers 46 will during the said movement of the slide 40 slide along the arms 80 causing the grippers to be forced inwards against the action of the springs in the housings 48. The conditions are further so that the grippers will slide into the opened sack. In the moment the rollers 4711 move onto the external face of the arms '80 the grippers 46 will catch hold of the sack so as to stretch its mouth and at the same time hold the sack fixedly which has until now been held by the suction pipes.

Due to the action of its drive members the turn-over buck 2 has been swung upwards and now assumes the position shown in Fig. 6 in which'its free end registers with the mouth of the open sack. The slide 40 carrying the grippers 46 now moves downwards the guides 39 and the grippers will consequently pull the sack 90' on to the turn-oven buck 2 (Fig.1 7 Immediately hereafter the free end of the turn-over buck will be lowered to the position shown in Fig. 8 so that thebottom of the sack drawn on to thezturn-over buck will be in front of the turn-ove-r'tork 19*(Fig. p p g V The turn-over buck'is now by itsv slide 21 moved against the bottom of the sack and will force said-bottom throughv the opening in the endofjthe turn-over buck. During the said movement'of the turn-over fork19 therollers will force the rods 27 inwards so that the rollers 28 of the latter will rest in the semisack is in the manner described pulled oifthe turn-over buck it will be passed, the outside out, onto the turn-over fork (Fig. 9). Due to the pressure exerted'by theturn-over fork against the bottom of the sack the sack will befreed from the spring actuatedgrippers'46.

VVhile-the turn-over fork performs: the said inverting operation on the sack the rods 27 which due to their S-shape are no longer under the action of the rollers 30, will swing outwardsand' will maintain the sack stretched during the inverting operation.

. On the slide 40 returning- (towards the left in Fig. '1) the bearing 7 8 on arm 41 will exertv a-pressure on the shoulder of rod 76 and the latter will then by way of the lever 73 and'thepull rod 75'move the arm" 63 downwards. The roller 72; ofarm 71 will thereby press against the arm 65 of: lever 65, 66 and will force the said arm upwards: sotha't the stop 67 on arm 65 will engage the shoulder 70 on arm 69 and will'thus be held against-the action of the spring in the -ho-us-= ing 68. The clamping device is now open- Theconditions are 'so' that the said opening operation of the clamping device will take place prior to the turn-over fork19 hav-' ing completed" the. inverting operation. At the end' of saidoperation the cross piece 23 on the turn-over fork will abut against the releasing arm 6% of. they clamping device. The arm69 will thereby be. forced away from the arm 65 and the sto-p 67 of the latter will be released from the shoulder 70 so Itliatthe jaw 66willd'ue to theacjtion of the spring in the housing6'8 smackaga inst'the aw6t The clampin bottom of the sack passed'onto the turn-over fork 19 by the jaws 64 and 66-catchingaround thesack in the recess 24 of 23 of the turn-over fork.

Simultaneously'with the turn-over fork IQ'finishingthe inverting of the sack the-free end; of the turn-ovr' buck will be raised, the

device is thusclamping' around the the cross piece- I Ml suction pipes stem 20 of the turn-over fork passing ating meansto subsequently separate said through the resilient flap 6 (Fig, bridge 5 of the turn-over buck.

(towards the right in Fig. 1) by its slide 21, while the clamping device will retain the Y The inverting operation proper has now open the jaws so that the inverted sack with been completed and there only remains to In testi .The turn-over fork will now be returned. tures.

its outside out can be released and drop down V into'a suitable collector. 1 V

The clampingdevice is as described above opened during the return movement of the slide 40 the treatment of the next to follow sack having already commenced, as described above, simultaneously with the inverting op- V eration of the first sack having been com- 'pleted. r

We claim.

.1. Ina sack inverting machine, a turnover buck and aturn-over fork coacting'with said buck to invert a sack drawn over said buck, a movable gripper device operableto draw a sack over said buck, and suctionv means arranged to coact with the edges of the-mouth of a sack to open the latter and 7 permit introduction of 3|! therein. v

' 2. In a sack inverting machine, aoturn-over the gripper device buck and aturn-over fork coacting with said 1 buck to invert a 'sack drawn over saidbuck,

a movable gripper device operable to draw a 7 8K sack over. said buck, and suction means arranged to coact with the edges of the mouth of a sack to open the latter and permit introduction of the grip-per device, therein, said suction means including upper and lower mouth.

, 3. In a sack inverting machine, a turn-over buck and a turn-overfork coacting with said buck to invert a sack drawn over saidbuck,

a sackover saidbuck, and suction-means arranged to coact with the edges of the mouth of a sack to open the latter and permit introduction of :the gripper device therein, said suction -means including upper and lower suction pipes, and means for moving said pipes apart to open the sack mouth.

4. In a sack inverting machine, aturn-over buck and a turn-over fork coacting with said buck to invert a sack drawn over said buck, a movable gripper device operable to draw movable apart to open the sack a movable gripper device operable to. draw 7 a sack over said buck, and suction means ar 7' ranged to coact with the edges of the mouth I of a sack to open the latter and permit in- I a I troduction of the grlpper device therein,

said suction means including upper and lowersuction pipes, means to create suction insaid pipes while the latter are arranged at the edges of the. mouth of a' fiat sack, and actu in the pipes to open the sack mouth.

mony whereof we afii'xour signa-- 

